1. Field of the Invention
The present invention relates to a water-sprinkling system for sprinkling water over lawn, moss or other crops and, more particularly, to an automatic water-sprinkling controller for controlling the water-sprinkling system so that the latter may automatically sprinkle the water for a predetermined time period when the shortage of water of the ground is sensed by the automatically water-sprinkling controller.
2. Description of the Prior Art
In the prior art, lawn, moss and so on are liable to wither, when the ground becomes short of water, so that they have to be watered many times a day, particularly in summer. This invites many disadvantges such as that the family cannot leave home for a trouble.
In recent years, there is available as means for eliminating those disadvantages an electromagnetic valve type water-sprinkling system which is equipped with a 24 hour timer. This system is acceptable as a convenience because it can be set with the water-sprinkling time period of 15 minutes, for example. However, the system has a drawback that it operates independently of the dryness of the ground, for example, it sprinkles the water even if it rains. Moreover, the system can hardly be used outdoor because its power supply uses an A.C. power source and has a problem in safety because its sprinkling operation is controlled by the A.C. power source.